The Marketcast Method for Aggregating Prediction Market Forecasts
We describe a hybrid forecasting method called marketcast. Marketcasts are based on bid and ask orders from prediction markets, aggregated using techniques associated with survey methods, rather than market matching algorithms. We discuss the process of conversion from market orders to probability estimates, and simple aggregation methods. The performance of marketcasts is compared to a traditional prediction market and a traditional opinion poll. Overall, marketcasts perform approximately as well as prediction markets and opinion poll methods on most questions, and performance is stable across model specifications.
KeywordsForecasting Prediction Markets Aggregation
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- 2.Mellers, B.A., Ungar, L.H., Baron, J., Ramos, J., Gurcay, B., Fincher, K., Scott, S., Moore, D., Atanasov, P., Swift, S., Tetlock, P.E.: Improving Geopolitical Forecasting with Teamwork, Training and Algorithms (manuscript under review)Google Scholar
- 3.Christiansen, J.D.: Prediction Markets: Practical Experiments in Small Markets and Behaviours Observed. J. of Prediction Markets. 1, 17–41 (2007)Google Scholar
- 5.Pennock, D.M.: A Dynamic Pari-Mutuel Market for Hedging, Wagering, and Information Aggregation. In: EC 2004 Proceedings of the 5th ACM Conference on Electronic Commerce, pp. 170–179. ACM, New York (2004)Google Scholar
- 7.Cliff, D., Bruten, J.: Zero Not Enough: On The Lower Limit of Agent Intelligence For Continuous Double Auction Markets. HP Laboratories Technical Report HPL (1997)Google Scholar
- 8.Othman, A.: Zero-intelligence agents in prediction markets. In: Proceedings of the 7th International Joint Conference on Autonomous Agents and Multiagent Systems, vol. 2, pp. 879–886. International Foundation for Autonomous Agents and Multiagent Systems (2008)Google Scholar
- 9.Wolfers, J., Zitzewitz, E.: Interpreting prediction market prices as probabilities (No. w12200). National Bureau of Economic Research (2006)Google Scholar
- 10.Satopaa, V.A., Baron, J., Foster, D.P., Mellers, B.A., Tetlock, P.E., Ungar, L.H.: Combining Multiple Probability Predictions Using a Simple Logit Model (Manuscript under review)Google Scholar
- 11.Page, L., Clemen, R.T.: Do Prediction Markets Produce Well Calibrated Probability Forecasts? Econ. J. (2012)Google Scholar
- 12.Rothschild, D.: Forecasting Elections: Comparing Prediction Markets, Polls, and Their Biases. Public Opinion Q. 73, 895–916 (2009)Google Scholar
- 13.Baron, J., Ungar, L.H., Mellers, B.A., Tetlock, P.E.: Two Reasons To Make Aggregated Probability Forecasts More Extreme (manuscript under review)Google Scholar
- 14.Servan-Schreiber, E., Wolfers, J., Pennock, D., Galebach, B.: Prediction Markets: Does Money Matter? Electronic Markets, 243–251 (2004)Google Scholar